1. Field of the Invention
The present invention relates to a method for driving a plasma display panel and, more particularly, to a method for driving a three-electrode surface-discharge alternating-current plasma display panel.
2. Description of the Related Art
FIG. 1 shows an electrode line pattern of a general three-electrode surface-discharge alternating-current plasma display panel, FIG. 2 shows a cell forming a pixel of the plasma display panel shown in FIG. 1, and FIG. 3 shows another example of a pixel of the panel shown in FIG. 1. Referring to the drawings, in a general three-electrode surface-discharge alternating-current plasma display panel, address electrode lines A1, A2, A3, . . . , Amxe2x88x922, Amxe2x88x921 and Am, a dielectric layer 11 (and/or 141 of FIG. 3), scan electrode lines Y1, Y2, . . . , Ynxe2x88x921 and Yn, common electrode lines X1, X2, . . . , Xnxe2x88x921 and Xn and a MgO protective film 12 are provided between front and rear glass substrates 10 and 13 of a general surface-discharge plasma display panel 1.
The address electrode lines A1, A2, A3, . . . , Amxe2x88x922, Amxe2x88x921 and Am, coat the entire surface of the rear glas substrate 13 in a predetermined pattern. Phosphors (142 of FIG. 3) may coat the entire surface of the scan electrode lines Y1, Y2, . . . , Ynxe2x88x921 and Yn. Otherwise, the phosphors 142 may coat the dielectric layer 141 in the event the dielectric layer is coated over the entire surface of the scan electrode lines Y1, Y2, . . . , Ynxe2x88x921 and Yn in a predetermined pattern.
The common electrode lines X1, X2, . . . , Xnxe2x88x921 and Xn and the scan electrode lines Y1, Y2, . . . , Ynxe2x88x921 and Yn are arranged on the rear surface of the front glass substrate 10, orthogonal to the address electrode lines A1, A2, A3, . . . , Amxe2x88x922, Amxe2x88x921 and Am in a predetermined pattern. The respective intersections define corresponding pixels. The common electrode lines X1, X2, . . . , Xnxe2x88x921 and Xn and the scan electrode lines Y1, Y2, . . . , Ynxe2x88x921 and Yn each comprise indium tin oxide (ITO) electrode lines Xna and Yna, and metal bus electrode lines Xnb and Ynb, as shown in FIG. 3. The dielectric layer 11 entirely coats the rear surface of the common electrode lines X1, X2, . . . , Xnxe2x88x921 and Xn and the scan electrode lines Y1, Y2, . . . , Ynxe2x88x921 and Yn. The MgO protective film 12 for protecting the panel 1 against strong electrical fields entirely coats the rear surface of the dielectric layer 11. A gas for forming a plasma is hermetically sealed in a discharge space.
The driving method generally adopted for the plasma display panel described above is an address/display separation driving method in which a reset step, an address step and a sustain discharge step are sequentially performed in a unit sub-field. In the reset step, wall charges remaining in the previous sub-field are erased. In the address step, the wall charges are formed in a selected pixel area. Also, in the sustain discharge step, light is produced at the pixel at which the wall charges are formed in the address step. In other words, if alternating pulses of a relatively high voltage are applied between the common electrode lines X1, X2, . . . , Xnxe2x88x921 and Xn and the scan electrode lines Y1, Y2, . . . , Ynxe2x88x921 and Yn, a surface discharge occurs at the pixel at which the wall charges are formed. Here, a plasma is formed in the gas layer of the discharge space 14 and the phosphors 142 are excited by ultraviolet rays to thus emit light.
Here, several unit sub-fields basically operating on the principles as described above are contained in a unit frame, thereby achieving a desired gray scale display by sustain discharge time intervals of the respective sub-fields.
In the sustain discharge step of the above-described method for driving the plasma display panel 1, conventionally, the timing of alternating pulses applied to all scan electrode lines Y1, Y2, . . . , Ynxe2x88x921 and Yn, are constant, and the timings of alternating pulses applied to all common electrode lines X1, X2, . . . , Xnxe2x88x921 and Xn is also constant.
Accordingly, since the overall driving current flowing at the timing at which alternating pulses are applied to all scan electrode lines Y1, Y2, . . . , Ynxe2x88x921 and Yn, or all common electrode lines X1, X2, . . . , Xnxe2x88x921 and Xn become considerably large, an apparatus for preventing electrical shock to the plasma display panel 1 and the driving apparatus (not shown) are further necessary. Also, electromagnetic interference increases.
To solve the above problem, it is an objective of the present invention to provide a method for driving a plasma display panel which can reduce electromagnetic interference without applying an electrical shock to a plasma display panel and a driving apparatus therefor.
Accordingly, to achieve the above objective, there is provided a method for driving a plasma display panel in which a reset step of erasing remaining wall charges from a previous sub-field, an address step of forming wall charges in a selected pixel area, and a sustain discharge step of generating light from pixels where the wall charges are generated in the address step by applying alternating pulses to scan electrode lines and common electrode lines arranged parallel to each other, are sequentially performed in a unit sub-field the method including the steps of allocating the scan electrode lines and the common electrode lines into a plurality of groups, and applying the alternating pulses to the scan electrode lines and common electrode lines allocated into each group in the address step.
In the sustain discharge step, the alternating pulses are preferably applied to the respective scan electrode lines and a common scan electrode which is not adjacent to the respective scan electrode lines at the same timing.
Therefore, since the amount of overall driving current flowing at a the timing at which alternating pulses are applied to all scan electrode lines Y1, Y2, . . . , Ynxe2x88x921 and Yn, or all common electrode lines X1, X2, . . . , Xnxe2x88x921 and Xn become considerably reduced, electrical shock to the plasma display panel and a driving apparatus therefor can be prevented and electromagnetic interference can be reduced.